Is Renewable Energy Reliable?

How Effective Are Renewable Energy Variables in Generating Electricity?

There’s a Perception:
“The effectiveness of renewable energy sources like solar power (PLTS) and wind power (PLTB) is highly dependent on the weather. Therefore, they are not as reliable as fossil fuels.”

However:
Countries like China, India, and Australia see the challenge of intermittency as something that can be overcome, for example, through energy storage, advanced grids, and integrated energy systems. China even has 887 GW of solar energy capacity, 521 GW of wind power, and 436 GW of hydropower (Enerdata, 2025). They are making variable renewable energy the backbone of their national energy systems.

Explanation:
Every energy source has its own inherent unreliability. Fossil fuels are unreliable due to their limited supply, price volatility, dependence on imports, and negative environmental impacts. Renewable energy, on the other hand, is intermittent, meaning its energy production fluctuates depending on natural factors such as weather and time of day.

Because of their intermittent nature, solar panel installation requires consideration of the solar intensity in a given area. Year-round exposure to sunlight will increase solar panel productivity. While cloudy weather or snowfall can reduce solar panel productivity, winter should not significantly impact the system’s annual energy generation (Blueraven.com, 2023).

Several ways to increase the efficiency of solar panels in generating electricity include (Sistinesolar.com, 2024):

  1. Choosing high-efficiency solar panels (~20%) is a key step in increasing the energy productivity of converting sunlight into electricity more efficiently than standard panels.
  2. To maximize solar panel efficiency, ensure they are properly oriented and tilted. In the Northern Hemisphere, face the panels south to capture maximum sunlight throughout the day. In the Southern Hemisphere, face the panels north.
  3. Be sure to keep solar panels clean to maximize their efficiency. Dust, dirt, leaves, and other debris can accumulate on the panel’s surface, reducing its ability to absorb solar energy. Not cleaning the panels can result in efficiency losses of up to 25-30%.
  4. Use mirrors to increase solar panel efficiency with a reflector system. Strategically place mirrors around the panels to direct and concentrate sunlight onto the panel’s surface, improving light exposure and panel performance.

Furthermore, to improve the reliability of solar energy, technological innovations such as energy storage or battery technology have been introduced to address the issue of intermittency.

In terms of time, a solar panel system can produce energy for 30 years, while an energy storage system like a battery can last up to 15 years. Here are some types of batteries that can be used to address the issue of intermittency in solar energy:

  1. Batteries: Energy storage systems using batteries are one of the most common solutions. Batteries can collect the energy generated by solar panels during periods of overproduction and store it for use when needed, such as during inclement weather or at night.
  2. Thermal Storage Systems (energy.gov, 2024): These systems use the heat generated by solar energy to heat a fluid or other medium. This heat can then be stored in a thermally insulated container and used later to generate electricity through a steam turbine or steam engine.
  3. Flywheels (atoenergi.com, 2024): Flywheels are mechanical devices that use kinetic energy to store energy. Energy from solar panels can be used to rotate the flywheel, which can then release this energy when needed.
  4. Supercapacitors (milkenreview.org, 2024): Supercapacitors are energy storage devices that can store and rapidly release large amounts of energy. They are suitable for applications where energy needs to be stored and released quickly, such as in situations where there are sudden fluctuations in solar energy production.
  5. Hydrogen and Synthetic Fuels (fscec.ucf.edu, 2024): Electrolysis processes can be used to produce hydrogen from water using solar energy. This hydrogen can then be stored and used to generate electricity via fuel cells when solar energy is not available.

IESR Words

  • “People often misunderstand the differences between individual power plants and the overall power generation system. When looking at individual power plants, combining variable renewable energy with battery storage is not yet a reliable and economical solution. However, when looking at the system as a whole, the variability of renewable energy becomes less significant due to the economies of scale of energy storage facilities and the ancillary services provided by other flexibility sources.”

    – Alvin Putra Sisdwinugraha, Power Systems and Renewable Energy Analyst, IESR

Description for

Children (14-18 years):

Solar energy is more reliable because it not only comes from unlimited sunlight, but is also more environmentally friendly than polluting fossil fuels. While solar energy is sometimes affected by weather conditions like clouds or rain, new technologies like energy storage and more efficient solar panels have made it increasingly reliable in generating electricity. This differs from fossil fuels, which have limited supplies, unstable prices, and negative environmental impacts like air pollution and climate change.

Can You Answer These Questions?

  1. What do you think is a good energy source for lighting an island?
  2. What is the impact of fossil fuels on the environment?
  3. Are coal reserves available forever?
  4. What will happen if coal reserves run out/are difficult to extract?
  5. What will happen if the price of imported coal increases?

Clean Energy Questions:

  1. What is the impact of solar energy on the environment?
  2. Is solar energy available forever?
  3. What will happen if it rains or becomes cloudy?
  4. What will happen if solar energy is equipped with power storage?

Description for

Adults (19 years and over):

Each type of energy has its own advantages and disadvantages. Fossil fuels, such as coal, face limitations in supply, price volatility, dependence on imports, and negative environmental impacts. On the other hand, renewable energy, such as solar energy, is intermittent because its production is affected by natural factors such as weather and time of day.

Solar energy is considered intermittent because its production fluctuates depending on sunlight exposure. However, high solar intensity throughout the year can significantly increase the productivity of solar panels. While adverse weather conditions such as cloudy skies or snowfall can reduce productivity, the impact of winter on the annual energy generation of a solar panel system should be insignificant.

To address the challenges of solar energy intermittency, technological innovations such as energy storage or batteries have been developed. These systems allow for the storage of excess energy from solar panels during the day for use when needed, thereby increasing the reliability of energy supply.

Energy choices for the future must consider not only reliability but also sustainability and long-term environmental impact.

PV power plants (PLTS) are less complex to maintain than coal-fired power plants. Furthermore, they contribute positively to the environment because they do not involve the combustion of fuels that produce greenhouse gas emissions. Unlike complex coal-fired power plants (PLTU) managed centrally by PLN (State Electricity Company), solar power plants (PLTS) offer a simpler and more environmentally friendly solution. You can manage their maintenance by regularly cleaning the solar panels, much like you would any other household appliance.